Influence of Equivalent Circuit Resistances on Operating Parameters on Three-Phase Induction Motors with Powers up to 50 kW

This work shows the results obtained from studying the influence of equivalent circuit resistances on three-phase induction motors. The stator resistance, rotor resistance, and iron losses resistance affect the different motor operating variables (output power, current, speed, power factor, starting ratios, and maximum torque). These influences have been quantified, paying particular attention to the losses affected and their impact on efficiency. The study carried out does not apply optimization techniques. It evaluates the different influences of the equivalent circuit’s different resistances on its operation by evaluating applicable constructive modifications concerning available motors. The work has been limited to three-phase induction motors up to 50 kW and low voltage, with the nominal powers of the selected motors being 0.25 kW, 1.5 kW, 7.5 kW, 22 kW, and 45 kW. The tools used to carry out the study are analyzing the equivalent circuit and the simulation of the electromagnetic structure using a finite-element program. The variations proposed in each resistance for all the motors studied is not purely theoretical, as it is based on applying feasible constructive modifications, appropriately analyzed and simulated. These modifications are the variation of the conductor diameter in the stator coils, the change of the section of the rotor cage, and the selection of different ferromagnetic steel types.

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Parametrization of Intelligent Relays SRW01 and Identification of Occurrence of Possible Failures in Actuation and Shutdown Operations of Electric Low-voltage Three-phase Induction Motors

IEEE Latin America Transactions ◽

10.1109/tla.2016.7785936 ◽

2016 ◽

Vol 14 (9) ◽

pp. 4076-4081

Author(s):

A.J.B. Agra

Keyword(s):

Induction Motors ◽

Low Voltage ◽

Three Phase

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Faults diagnosis in stator windings of high speed solid rotor induction motors using fuzzy neural network

International Journal of Power Electronics and Drive Systems (IJPEDS) ◽

10.11591/ijpeds.v12.i1.pp597-611 ◽

2021 ◽

Vol 12 (1) ◽

pp. 597

Author(s):

Ahmed Thamer Radhi ◽

Wael Hussein Zayer

Keyword(s):

Neural Network ◽

Equivalent Circuit ◽

High Speed ◽

Fuzzy Neural Network ◽

Induction Motors ◽

Stator Winding ◽

Three Phase ◽

Fuzzy Neural ◽

Diagnosis Method ◽

Faults Diagnosis

The paper deals with faults diagnosis method proposed to detect the inter-turn and turn to earth short circuit in stator winding of three-phase high-speed solid rotor induction motors. This method based on negative sequence current of motor and fuzzy neural network algorithm. On the basis of analysis of 2-D electromagnet field in the solid rotor the rotor impedance has been derived to develop the solid rotor induction motor equivalent circuit. The motor equivalent circuit is simulated by MATLAB software to study and record the data for training and testing the proposed diagnosis method. The numerical results of proposed approach are evaluated using simulation of a three-phase high-speed solid-rotor induction motor of two-pole, 140 Hz. The results of simulation shows that the proposed diagnosis method is fast and efficient for detecting inter-turn and turn to earth faults in stator winding of high-speed solid-rotor induction motors with different faults conditions

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Complex Electronic Protection for Low-voltage Three-phase Induction Motors

WSEAS TRANSACTIONS ON ELECTRONICS ◽

10.37394/232017.2020.11.2 ◽

2020 ◽

Vol 11 ◽

pp. 11-17

Author(s):

Gabriel Nicolae Popa ◽

Corina Maria Diniș

Keyword(s):

Induction Motors ◽

Low Voltage ◽

Short Circuit ◽

Electronic Devices ◽

General Purpose ◽

Two Phase ◽

Dc Voltage ◽

Electric Drives ◽

Normal Limits ◽

Three Phase

Low-voltage three-phase induction motors are most often used in industrial electric drives. Electric motors must be protected by electric and/or electronic devices against: short-circuit, overloads, asymmetrical currents, two-phase voltage operation, under-voltage, and over-temperature. To design the electronic protection currents, voltages and temperature must be measured to determine whether they fall within normal limits. The electronic protection was design into low capacity PLC. The paper presents the designs and analysis of complex electronic protection for general purpose low-voltage three-phase induction motors. The electronic protection has Hall transducers and conversion electronic devices for AC currents to DC voltages, AC voltages to DC voltage, temperature to DC voltage, a low capacity PLC, switches, motor’s power contactors, and signalling lamps has been developed. Experiments with complex electronic protection, for different faults are presented. The proposed protection has the advantages of incorporating all usual protections future for the low-voltage three-phase induction motors.

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